Botulinum Toxin A for the Management of Post-Laryngectomy Salivary Leak and Pharyngocutaneous Fistula: A Case Series and Narrative Review

Post-laryngectomy salivary leak and pharyngocutaneous fistula (PCF) are recognised complications that prolong hospitalisation, delay adjuvant treatment and, in severe cases, risk major vessel exposure; current management relies on conservative measures or systemic anticholinergic agents, which carry a substantial burden of unwanted effects. We present four consecutive patients treated with a standardised regimen of botulinum toxin A (BoNT) injected into the parotid tail, parotid body and submandibular gland after failure of conservative management for post-laryngectomy salivary leak/PCF; all four achieved clinical and radiological resolution without significant local or systemic complications. We conducted a narrative review of the literature (PubMed, EMBASE, Cochrane, Google Scholar) using a structured search and screening process, screening 1198 records (701 after deduplication) and identifying 13 eligible studies (231 patients who received BoNT across 12 primary studies) evaluating BoNT for salivary leak/fistula across post-laryngectomy PCF and post-parotidectomy sialocele/fistula populations. A previous systematic review is discussed as supporting context; its patient cohort is not included in the total above, as its 27 source articles may overlap with the primary studies included in this review. Across the case series and a limited, predominantly observational literature base, BoNT was associated with rapid salivary suppression (up to ~95% reduction in one study), high fistula closure rates (54–100%), and accelerated healing, including a statistically significant reduction in healing time in one comparative study (18.5 vs. 26 days, p = 0.008); adverse events were reported as rare and minor, though these findings warrant cautious interpretation given the evidence base. BoNT injection is a low-risk, potentially high-yield adjunct for post-laryngectomy salivary leak and PCF, avoiding the systemic anticholinergic burden of alternative pharmacological treatments; multicentre studies with standardised dosing protocols are needed to establish its role in standard practice.